Workshop-Specific Instructions

The following comprises workshop-specific instructions and details for the LDM Training Workshop.

Create the LDM user-account

An account for the LDM user should already exist on your workstation.

Ensure that TCP connections can be made

This should already have been done.

Become the LDM user in the user's home-directory

If you became root by executing the su command as the LDM user in a terminal window, then simply execute the command exit in the terminal window; otherwise, log off the computer and log in as the LDM user.

Edit the LDM user's profile-file

This should already have been done. You can verify this with the command

      cat .bash_profile

Build and Install the Distribution

If bash(1) is your user-shell (which is the default) then do the following:

      cd
      wget https://downloads.unidata.ucar.edu/ldm/6.15.0/ldm-6.15.0.tar.gz
      gunzip -c ldm-6.15.0.tar.gz | pax -r '-s:/:/src/:'
      cd ldm-6.15.0/src
      ./configure >&configure.log && echo Configured && make install >&install.log && echo Installed

Otherwise, do the equivalent of the above for your user-shell.

Vet the LDM registry

The default values are fine.

For average rates of the various feedtypes, see, for example, the data-volume summary webpage for a computer at the UPC.

Request authorization at the upstream LDM

Add the following entry to the file $HOME/etc/ldmd.conf to allow all workshop LDM-s to obtain data from any workshop LDM:

      ALLOW	ANY	^workshop[0-9]{2}\.fl-guest\.ucar\.edu$

For reference, see LDM Basics: ldmd.conf.

Edit the LDM configuration-file, etc/ldmd.conf

The "EXEC pqact" entry should already be enabled to allow local processing of received data-products.

Add the following entries to the LDM configuration file, ldmd.conf, to request the IDS|DDPLUS and NEXRAD3 data-feeds from the instructor's LDM:

      REQUEST	IDS|DDPLUS	.*	workshop01.fl-guest.ucar.edu
      REQUEST	NEXRAD3		.*	workshop01.fl-guest.ucar.edu

For reference, see LDM Basics: ldmd.conf.

Edit the pqact configuration-file, etc/pqact.conf

Ensure that the following is the only active entry:

      IDS|DDPLUS
	    ^(..)(..).. .... (..)(..)
	    FILE
	    IDS_DDPLUS/\1/\2/(\3:yyyy)(\3:mm)(\3:dd)T\4.txt

Remember to start the continuation-lines with a tab character!

This entry will file data-products of feedtype IDS|DDPLUS in an appropriate directory hierarchy with the canonical time of the data-product as the file name.

For reference, see LDM Basics: pqact.conf.

Edit the scour configuration-file, etc/scour.conf

Add the following line to the scour(1) configuration-file, etc/scour.conf:

      IDS_DDPLUS 1

This will remove all files in the data directory hierarchy that are older than one day.

For reference, see LDM Basics: scour.conf.

Edit the LDM-user's crontab(1) file

Add the following lines via the command "crontab -e":

      0 * * * * bin/ldmadmin scour >/dev/null
      0 0 * * * bin/ldmadmin newlog
      * * * * * bin/ldmadmin addmetrics
      * * 0 0 0 bin/ldmadmin newmetrics
      0,15,30,45 * * * * bin/ldmadmin check >/dev/null

Ensure that the LDM is started at boot-time

We're not concerned about restarting the LDM at boot-time for this workshop. So we'll skip this step.